1. Field of the Invention
The present invention relates generally to the management of telecommunications cabling, and more specifically, to a fuse-protected cross-connect drawer to facilitate telephone and data communications service.
2. Description of the Relevant Art
Wiring drawers are currently used by telecommunications companies for connecting copper telephone/data communications wires from a telephone company office to a user""s site. Wiring panels provided as pull-out drawers, that incorporate fuse protection panels only, are already known. Such drawers are typically arranged in a support framework or cabinet in side-by-side fashion. One of such drawers can be extended from the framework or cabinet to expose a front face of the drawer in which a plurality of removable fuses are inserted into sockets. These fuses protect the telephone company""s office equipment from lightning strikes or power surges that occur at the customer site. These fuse protection drawers are typically located in an underground equipment vault known as a Controlled Environment Vault (CEV) owned by the telephone company. They may also be installed at the telephone company central office. In the case of very large customers, such as hotels or high-rise office buildings, such fuse protection drawers may be installed at the user site. However, when a customer needs to add lines, or change their service, it is typically necessary for the telephone technician to go to a separate equipment board located at the customer""s site, or just outside the customer""s site. The equipment board has a series of terminal pin blocks that the technician works on to determine what lines go to which wall jack in a user""s facility. The technician can xe2x80x9cwire-wrapxe2x80x9d the ends of connecting wires to the various pins on a terminal pin block to configure the customer""s service.
In the past, the wiring of the fuse protection panels was fairly straightforward, in that the incoming and outgoing lines were dedicated to particular customers of the local service provider. The fuse protection drawers did not need to provide any change-of-service functions since the incoming and outgoing lines were dedicated, and since any changes in service could be accommodated at or adjacent the user""s site. More recently, as a result of deregulation, local service provider telephone companies have found that they can not dedicate incoming and outgoing lines for a particular customer. For example, a local telephone service provider may now be obligated to lease lines in the underground equipment vault to competitive signal carriers.
There is obviously a limited amount of space in such underground vaults, and the aforementioned wiring drawers used to support fuse protection blocks should ideally be capable of handling a relatively large number of incoming and outgoing signal lines to maintain a high density. At the same time, such wiring drawers must keep such large number of incoming and outgoing signal wires organized so that telephone company technicians can efficiently locate particular lines within the underground vault in order to properly maintain, modify, and diagnose such signal lines.
Accordingly, it is an object of the present invention to provide a high density drawer assembly for telecommunications wires which includes fuse protection for such lines.
Another object of the present invention is to provide such a drawer assembly which conveniently organizes a relatively large number of incoming and outgoing telecommunication lines for easy identification.
Still another object of the present invention is to provide such a high-density drawer assembly that provides ready and convenient access to each incoming and outgoing line in order to efficiently maintain, modify, and diagnose the telecommunications system.
A further object of the present invention is to provide such a drawer assembly that includes both fuse protection and the ability to flexibly configure, or modify, the coupling between a particular incoming line and a particular outgoing line, all within the same drawer assembly.
A still further object of the present invention is to provide an improved latching mechanism for selectively retaining the drawer assembly within its supporting framework until a technician needs to access such drawer assembly.
These and other objects of the present invention will become more apparent to those skilled in the art as the description of the present invention proceeds.
Briefly described, and in accordance with a preferred embodiment thereof, the present invention relates to a pull-out drawer assembly for interconnecting telecommunications wiring, including a support frame and at least one drawer slidingly supported thereby for movement between a stored position and an extended position projecting from the support frame. A first grouping of telecommunications lines extends into the support frame and are coupled to the drawer; this first group of lines might be, for example, incoming lines from a telephone company central office to provide telecommunications services. A second grouping of telecommunications lines also extends into the support frame and are also coupled to the drawer; this second group of lines might be, for example, outgoing telecommunications lines extending to a user premises.
In the preferred embodiment of the present invention, each pull-out drawer includes a series of fuse protection blocks mounted to the drawer. The fuse protection blocks each provide sockets for receiving removable fuses that protect against lightning strikes and/or power surges. Ideally, each of the incoming telecommunications lines is coupled to one of such sockets to protect such incoming line. The preferred form of the present invention also includes a series of terminal pin blocks mounted to each pull-out drawer. These terminal pin blocks are provided with wiring pins, and these wiring pins can be independently assigned to particular incoming or outgoing lines. In the case of incoming lines, the wiring pin preferably is wired through one of the aforementioned fuse sockets before reaching the incoming line to ensure fuse protection of the central office equipment.
The fuse protection blocks each have a first generally-planar face presenting the fuse protection sockets on a first side of the pull-out drawer, and an opposing rear face from which wiring terminals extend on the opposing second side of said drawer. Likewise, the terminal pin blocks each have a first generally-planar face from which the wiring pins extend in a first direction from the first side of the drawer, and an opposing rear face from which the wiring pins extend in an opposing second direction from the second side of the drawer. The first face of each fuse protection block and the first face of each terminal pin block generally lie within a common plane along the first side of the drawer.
The wiring terminals of the fuse protection blocks, and the wiring pins on the second sides of the terminal pin blocks, can be pre-wired. For example, an incoming line can be electrically coupled with a first terminal of a fuse protection socket, and a connection wire can be installed between the second terminal of the fuse protection socket and one of the wiring pins of a terminal pin block. Likewise, an outgoing line can be pre-wired to one of the wiring pins on the second side of a terminal pin block. On the other hand, the pull-out drawer assembly of the present invention is adapted to receive a series of configuration wires that can be installed by a telephone technician, and which extend between specified pairs of wiring pins along the first side of the drawer. In this manner, for example, a technician can provide an additional line to a customer merely by adding a configuration wire on the first side of the drawer between the wiring pin that leads to a fuse protection socket associated with an unused incoming line, and the wiring pin for an outgoing line leading to the user""s premises.
In the preferred embodiment of the present invention, a wiring raceway is provided proximate the terminal pin blocks on the first side of the drawer for guiding the aforementioned configuration wires between their respective wiring pins. The wiring raceway includes a planar base for being secured to the first side of said drawer; outwardly-directed fingers extend from opposing first and second side edges of the base. These fingers are spaced apart from one another to permit configuration wires to be inserted therebetween through either side of the wiring raceway. In the preferred form of the present invention, each of such fingers includes a tab that projects toward a correspondingly-shaped cut-out in the next-adjacent finger for allowing a technician to insert configuration wires between the adjacent fingers, while keeping previously inserted configuration wires in place. Ideally, a first finger on one side of the raceway and a second finger on the second side of the raceway converge toward each other to form a protective overpass, or arch, above the base of the wiring raceway to help protect the wiring inside. Preferably, the fingers that form such overpass are spaced from each other by a slot which extends at an angle to the wiring raceway for allowing configuration wiring to be passed through the protective overpass.
In order to achieve a high packing density, the drawer assembly preferably includes a drawer framework, and a series of braces extend across the drawer framework spaced apart from each other by the width of the terminal pin blocks. This allows the terminal pin blocks to be supported from first and second opposing edges thereof between two successive braces.